Cotap, a startup launched last year that provides a WhatsApp-like messaging service for the workplace, has integrated its product with four leading cloud storage providers and released a desktop app, as it jockeys for position in the enterprise communications market.

Cotap, led by two former Yammer executives, has linked its product with Box, Dropbox, Google’s Drive and Microsoft’s OneDrive, to simplify how users can share files kept in these cloud storage services. The integration was built using Box’s View API, which delivers what Cotap describes as “high quality” mobile rendering of the files that are shared and launched.

Initially available as a mobile app for Android and iOS devices, the Cotap service can now be accessed via web browsers and from a desktop tool for Mac OS X laptop and desktop computers. This way, the Cotap service is available via a broader selection of devices, a must for professionals who do work across smartphones, tablets and computers. Actions are synchronized in real time across a user’s devices.

Cotap also fine-tuned navigation, letting users pin links to the groups and co-workers they interact with the most or consider the most important to their work.

Cotap positions its service as a better option to standard mobile text messaging, because it requires its subscribers to sign up with their work email address, and then groups them accordingly in a directory, letting them communicate on a one-on-one or one-to-many basis without them having to know each other’s mobile phone numbers. In addition to text messages, they can also send images.

Its messaging service is in use in about 10,000 companies, with deployments varying in size and scope.

End users can install the Cotap app for free, but the company also offers corporate licenses that give IT administrators a web-based console. The Team edition costs $5 per user per month and includes alerts and usage analytics data, while the Enterprise edition, at $10 per user per month, adds user and data management, and activity monitoring.

Later, Cotap plans to add integration with Microsoft’s Active Directory and with popular mobile device management (MDM) tools so that IT pros can manage the Cotap service from the same central location that they manage other apps and services, so that, for example, revoking a departing employee’s access can be done once for Cotap and all other wares.

Asked about Cotap competitors, co-founder and CEO Jim Patterson says there are many niche players, but he also mentions mature products entrenched in workplaces that offer more than enterprise messaging, like Microsoft’s Lync unified communications server and Cisco’s WebEx.

Tools like Lync and WebEx aren’t mobile friendly, which is why plain vanilla text messaging isn’t used a lot for work, even though most people bring a smartphone to the office, he said. That’s the opportunity Cotap is trying to exploit. “We started with the mobile apps. That’s a big difference,” said Patterson, who was Yammer’s chief product officer. With the enhancements unveiled on Wednesday, Patterson considers that the company is branching out from exclusively messaging into broader productivity.

Despite the pedigree of its leaders—the other co-founder, Zack Parker, was senior director of engineering at Yammer—and its early funding success—$15.5 million [m] to date—the 35-person startup has a tough road ahead to find its place among giant enterprise vendors.